Changes in small artery structure characterized by an increased wall-to-lumen ratio (WLR) are characteristic feature of target organ damage in hypertension. (3; 4). A clinical study examining small arteries obtained from gluteal biopsies of patients with hypertension revealed that an increased WLR of subcutaneous small arteries is one of the first manifestations of target organ damage in hypertension that occur before proteinuria and cardiac hypertrophy (5). Of clinical importance, structural arteries of small subcutaneous arteries have been shown to be of prognostic significance, with adverse prognosis in subjects with higher WLR (6-8). However, the assessment of arteriolar structure from biopsies of subcutaneous tissue is invasive and impractical in clinical practice. A new approach focuses on retinal arteriolar structural parameters by using scanning laser Doppler flowmetry (SLDF) with automatic full-field perfusion imaging analyses (9). This approach allows the non-invasive assessment of both the outer diameter and inner diameter of retinal arterioles in vivo and, thus, analyses vascular remodeling of retinal arterioles by calculating WLR = (outer diameter - inner diameter) / inner diameter) (10).